Manhattan, Kansas
June 14, 2005
Kansas State University
(K-State) and the Kansas Wheat Commission are spearheading the
effort to create the Wheat Genome Sequencing Consortium, an
international program focused on building the foundation for
advancing agricultural research for wheat production.
The principal goal of the
consortium is to obtain a publicly available, complete sequence
of common (hexaploid) wheat since it is grown on more than 95
percent of the wheat-growing-area worldwide.
Bikram Gill, university
distinguished professor of plant pathology at K-State and the
U.S. co-chair of the consortium, said wheat should be next in
line for the sequencing process.
"Among the three major crops:
rice, maize and wheat, the rice and maize genomes have already
been sequenced," he said. "Right now, there is very little
effort for wheat and it is getting behind. The reason is that
the wheat genome is very large. It is 40-times larger than the
rice genome and six-times larger than the maize genome."
The complete sequence of common
wheat holds the key to genetic improvements that will allow
growers to meet the growing demand for high-quality food
produced in an environmentally sensitive, sustainable and
profitable manner, he said.
Gill said understanding the
sequencing process is as important to understanding wheat
genomes as learning the alphabet is in learning the English
language.
"Essentially, there are four
chemical letters called bases -- A, C, G and T -- in the DNA
code that controls wheat genetic traits," he said. "There are 16
billion base pairs in wheat. To learn the language of genetic
traits we must determine the exact sequence of the four letters
in the wheat genomes."
In the future, members of the
consortium will begin identifying all 16 billion sequences, but
for now the program is in the process of plotting out physical
maps of small sequences. This is just one of the short-term
goals laid out by the consortium.
The organization believes that
its goal of obtaining a complete sequence of common wheat for a
reasonable price is achievable in the foreseeable future. In
late 2003, the cost of obtaining coverage of a genome equivalent
in size to the human genome was approximately $45 million.
Within 18 months, the cost was less than $18 million at any of
the large sequencing centers. New sequencing methods that are
under development may reduce further sequencing costs in the
future, Gill said. |